conceptual scheme proposed by Spengler for the analysis of the factors affecting the decision to have children. In this scheme, the decision to have an additional child, or voluntary fertility constraint, is a function of three variables: the preference system, the price system, and income (38).
Heer (39) defines these terms broadly. The preference system describes the value which a married couple places on additional children relative to all other goals they strive to achieve without the child; the price system indicates the net costs of an additional child relative to the costs of attaining all other goals without an additional child; and income, the total resources expendable for goal pursuit, includes not only monetary income but the total amount of time and energy that a couple has for pursuit of all their possible goals in life. Heer postulates that the probability of deciding to have an additional child is directly related to the anticipated value of this child and the total resources available for all goals and inversely related to the predicted cost of an additional child. The configuration of these variable relationships determines whether an additional child is considered an asset or liability.
The Increasing Economic Liabilities of an Additional Child
The social and economic changes in developing countries—measured by their impact upon the preference system, the price system, and income-have brought about a general reversal in attitudes toward children as economic assets. In the past the assurance of a surviving son, the economic gain from child labor, and the guarantee that family members would be cared for in their old age have held high priority in the preference system. These norms have encouraged high fertility in transitional societies. Demographic and social changes, such as declining infant mortality, child welfare, compulsory education, and social security schemes, have gradually replaced traditional values with small family norms and low fertility.
Concomitantly, changes in the price system have tended to negate the economic advantages of the large family. The rising costs of housing as a frequent side effect of urbanization, longer periods of child dependency as the result of an expanded educational system, as well as the increasing cost of child care for working mothers, are additional factors which may cause the birth of another child to be an economic liability.
The economic pressure of additional children upon the family has been instrumental in initiating efforts to limit family size. Resorting to abortion continues to be a sure method of terminating an unwanted pregnancy, even though traditional and modern methods of contraception may be used.
Economic motivation to limit family size has been invoked as the reason for abortion in many countries, regardless of the type of abortion law. Nozue (41) reported that 63 percent of all abortions in Japan are performed for socioeconomic reasons. A more intensive study by Koya (42) indicated that